Asana-Math: close but no cigar

[Vasile Gaburici]

As for the "developed specifically for Cambria" that's a myth. If you
want to make statements like that, it's more appropriate to say that
TeX was designed for CM. There are 22 dimensions for a TeX math font.
There are over 50 dimensions ("constants") for an OpenType MATH table,
and some of them are lists! The MS folks in charge of this have stated
on their blogs & typophile that they wanted to move most of the TeX
built-in constants into the font. They were not kidding.

MATH table flexibility does not stop there, you can have as many size
variants as you like say for parentheses or radicals; these are
specified as lists; unlike TeX there are no built-in rules for
choosing the next "bigger" glyph from the font. Asana makes good use
of this, there are up to 5-6 variants for things like widehats, tildes
etc. When it runs out of the pre-designed stuff, it applies a
construction rule that's also defined via lists, although this isn't
anymore flexible than TeX AFAICT. You are limited to horizontal and
vertical constructions.

There's also a sub-table specifying alignment axis for math accents.
This differs from how mark or mkmk work. The positioning info is
shared between the accent and the letter. I don't think TeX has this
at all. There's also some adjustment field, but fontforge crashes if
you click on it :(

On Wed, Aug 13, 2008 at 12:29 PM, Dave Crossland <dave at lab6.com> wrote:
> 2008/8/13 Vasile Gaburici <vgaburici at gmail.com>:
>>
>> The math script, aka MATH table, is a
>> MS extension to OpenType. MS has not yet officially submitted any
>> documentation for these math layout extensions -- and they are quite
>> extensive -- not even in the draft 1.5/1.6 OpenType spec. Despite
>> this, it is the de-facto OpenType math standard, and support for it
>> has appeared in FOSS projects.
>>
>> These extensions are implemented only in the Cambria Math font (MS),
>> and now in Asana Math (FOSS).
>
> AIUI, the MATH table in Cambria is developed specifically for Cambria
> and will not be a 100% fit for other fonts; this is hy MS hasnt done
> anything about documenting it properly.
>
> Dave
>
>